
PRIUS_OM_OM47F01U_(U)
5236-3. Do-it-yourself maintenance
6
Maintenance and care
WARNING
■When disconnecting the 12-volt battery
Do not disconnect the negative (-) terminal on the body side. T he discon-
nected negative (-) terminal may touch the positive (+) terminal, which may
cause a short and result in death or serious injury.
NOTICE
■ When recharging th e 12-volt battery
Never recharge the 12-volt battery while the hybrid system is o perating.
Also, be sure all accessories are turned off.

PRIUS_OM_OM47F01U_(U)
5496-3. Do-it-yourself maintenance
6
Maintenance and care
■Scheduled maintenance of the air intake vent is necessary when
In some situations such as when the vehicle is used frequently or in heavy
traffic or dusty areas, the air intake vent may need to be cleaned more regu-
larly. For details, refer to the “Scheduled Maintenance Guide” or “Owner’s
Manual Supplement”.
■ Cleaning the air intake vent
●Dust in the air intake vent may interfere with the cooling of t he hybrid battery
(traction battery). If charging/discharging of the hybrid battery (traction bat-
tery) becomes limited, the distance that the vehicle can be driven using the
electric motor (traction motor) may be reduced and the fuel economy may
be reduced. Inspect and clean the air intake vent periodically.
● Improper handling of the air intake vent cover and filter may result in dam-
age to them. If you have any concerns about cleaning the filter, contact your
Toyota dealer.
■ If “Maintenance Required for Traction Battery Cooling Parts See Owner’s
Manual” is shown on the mu lti-information display
● If this warning message is shown on the multi-information displ ay, remove
the air intake vent cover and clean the filter. ( P. 546)
● After cleaning the air intake vent, start the hybrid system and check that the
warning message is no longer shown.
It may take approximately 20 minutes after the hybrid system is started until
the warning message disappears. If the warning message does not disap-
pear, have the vehicle inspected by your Toyota dealer.
WARNING
■When cleaning the air intake vent
● Do not use water or other liquids to clean the air intake vent. If water is
applied to the hybrid battery (traction battery) or other compo nents, a mal-
function or fire may occur.
● Before cleaning the air intake vent, make sure to turn the power switch off
to stop the hybrid system.
■ When removing the air intake vent cover
Do not touch the service plug located near the air intake vent. ( P. 92)

550
PRIUS_OM_OM47F01U_(U)
6-3. Do-it-yourself maintenance
NOTICE
■When cleaning the air intake vent
■ To prevent damage to the vehicle
● Do not allow water or foreign matter to enter the air intake ve nt when the
cover is removed.
● Carefully handle the removed filter so that it will not be damaged. If the fil-
ter is damaged, have it replaced with a new filter by your Toyota dealer.
● Make sure to reinstall the filter and cover to their original positions after
cleaning.
● Do not install anything to the air intake vent other than the exclusive filter
for this vehicle or use the vehicle without the filter installe d.
■ If “Maintenance Required for Traction Battery Cooling Parts See
Owner’s Manual” is shown on the multi-information display
If the vehicle is continuously driven with the warning message (indicating
that charging/discharging of the hybrid battery [traction batte ry] may
become limited) displayed, the hybrid battery (traction battery ) may mal-
function. If the warning message is shown, clean the air intake vent immedi-
ately.
When cleaning the air intake vent, make
sure to only use a vacuum to suck out
dust and clogs. If a compressed air blow
gun, etc. is used to blow out dust and
clogs, the dust or clogs may be pushed
into the air intake vent, which may affect
the performance of the hybrid battery
(traction battery) and cause a malfunc-
tion.

588
PRIUS_OM_OM47F01U_(U)
7-2. Steps to take in an emergency
If a warning light turns on or a war ning
buzzer sounds
Calmly perform the following actions if any of the warning ligh ts
comes on or flashes. If a light comes on or flashes, but then
goes off, this does not necessarily indicate a malfunction in the
system. However, if this continues to occur, have the vehicle
inspected by your Toyota dealer.
Warning light and w arning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning light and warning buzzer (red
indicator)
*1
Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer. Continuing to drive the vehi-
cle may be dangerous.
Brake system warning light (yellow indicator)
Indicates a malfunction in:
• The regenerative braking system; or
• The electronically controlled brake system
Have the vehicle inspected by your Toyota dealer
immediately.
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer.
Low engine oil pressure warning light
(warning buzzer)
*2
Indicates that the engine oil pressure is too low
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer.
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system; or
• The electronic throttle control system
Have the vehicle inspected by your Toyota dealer
immediately.

6037-2. Steps to take in an emergency
PRIUS_OM_OM47F01U_(U)
7
When trouble arises
■If “Shift System Malfunction See Owner’s Manual” is shown
Indicates a malfunction in the shift control system. Immediatel y have the sys-
tem inspected by your Toyota dealer.
The system may not operate properly.
■ If “Low 12-Volt Battery Apply Parking Brake Securely While Park ing See
Owner’s Manual” is shown
Indicates that the 12-volt battery charge is insufficient. Char ge or replace the
12-volt battery.
● When the message is shown, the hybrid system may not start or t he shift
position may not be changed normally. (Coping method: P. 606)
● After charging the 12-volt battery, the message may not go off until the shift
position is changed from P.
■ If “Shifting Unavailable Low 12-Volt Battery See Owner’s Manual ” is
shown
Indicates that the shift position cannot be changed because the voltage of the
12-volt battery drops. Charge or replace the 12-volt battery.
(Coping method in the case the 12-volt battery is discharged: P. 646)
■ If “Hybrid System Overheated. Reduced Output Power.” is shown
The message may be shown when driving under severe operating co nditions.
(For example, when driving up a long steep hill or driving up a steep hill in
reverse.)
Coping method: P. 652
■ If “Maintenance Required for Traction Battery Cooling Parts See Owner’s
Manual” is shown
The filter may be clogged, the air intake vent may be blocked or there may be
a gap in the duct.
● If the air intake vent is dirty, refer to P. 546 for information on how to clean
the air intake vent.
● If the message is shown when the air intake vent is not dirty, have the vehi-
cle inspected by your Toyota dealer.
■ If “Traction Battery Needs to be Protected Refrain From the Use of
Position” is shown
This message may be displayed when the shift position is in N.
As the hybrid battery (traction battery) can not be charged when the shift
position is in N, shift the shift position to P when the vehicle is stopped.
■ If “Traction Battery Needs to be Protected Shift into to Resta rt” is
shown
This message is displayed when the hybrid battery (traction battery) charge
has become extremely low because the vehicle has been left with the N shift
position selected for a certain amount of time.
When operating the vehicle, shift to P and restart the hybrid s ystem.

6487-2. Steps to take in an emergency
PRIUS_OM_OM47F01U_(U)
Once the hybrid system has started, remove the jumper cables in
the exact reverse order from which they were connected.
To install the engine cover, conduct the removal procedure in
reverse. After installing, check that the fixed pins are inserted
securely.
Once the hybrid system starts, have the vehicle inspected at yo ur
Toyota dealer as soon as possible.
■ When opening the cover of the positive (+) battery terminal
P. 521
■ Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting.
■ To prevent 12-volt battery discharge
●Turn off the headlights and the audio system while the hybrid s ystem is off.
● Turn off any unnecessary electrical components when the vehicle is running
at a low speed for an extended period, such as in heavy traffic .
■ When the 12-volt battery is removed or discharged
● Information stored in the ECU is cleared. When the 12-volt batt ery is
depleted, have the vehicle inspected at your Toyota dealer.
● Some systems may require initialization. ( P. 697)
■ When removing the 12-vo lt battery terminals
When the 12-volt battery terminals are removed, the information stored in the
ECU is cleared. Before removing the 12-volt battery terminals, contact your
Toyota dealer.
■ Charging the 12-volt battery
The electricity stored in the 12-volt battery will discharge gr adually even when
the vehicle is not in use, due to natural discharge and the dra ining effects of
certain electrical appliances. If the vehicle is left for a lon g time, the 12-volt
battery may discharge, and the hybrid system may be unable to s tart. (The
12-volt battery recharges automatically while the hybrid system is operating.)
7
8

6497-2. Steps to take in an emergency
PRIUS_OM_OM47F01U_(U)
7
When trouble arises
■When recharging or replacing the 12-volt battery
●In some cases, it may not be possible to unlock the doors using the smart
key system when the 12-volt battery is discharged. Use the wire less remote
control or the mechanical key to lock or unlock the doors.
● The hybrid system may not start on the first attempt after the 12-volt battery
has recharged but will start normally after the second attempt. This is not a
malfunction.
● The power switch mode is memorized by the vehicle. When the 12- volt bat-
tery is reconnected, the system will return to the mode it was in before the
12-volt battery was discharged. Before disconnecting the 12-volt battery,
turn the power switch off.
If you are unsure what mode the power switch was in before the 12-volt bat-
tery discharged, be especially careful when reconnecting the 12 -volt battery.
● If the 12-volt battery discharges while the shift position is in P, it may not be
possible to shift the shift position to other positions. In thi s case, the vehicle
cannot be towed without lifting both front wheels because the f ront wheels
will be locked. ( P. 580)
■ When replacing the 12-volt battery
●Use a 12-volt battery that conforms to European regulations.
● Use a 12-volt battery that the case size is same as the previou s one (LN1),
20 hour rate capacity (20HR) is equivalent (45Ah) or greater, and perfor-
mance rating (CCA) is equivalent (295A) or greater.
• If the sizes differ, the 12-volt battery cannot be properly se cured.
• If the 20 hour rate capacity is low, even if the time period w here the vehi-
cle is not used is a short time, the 12-volt battery may discharge and the
hybrid system may not be able to start.
● For details, consult your Toyota dealer.

666
PRIUS_OM_OM47F01U_(U)
8-1. Specifications
*: The coolant capacity is a reference quantity.If replacement is necessary, contact your Toyota dealer.
Cooling system
Capacity*
Gasoline
engine6.6 qt. (6.2 L, 5.5 Imp.qt.)
Power
control unit1.5 qt. (1.4 L, 1.2 Imp.qt.)
Coolant type
Use either of the following: • “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-silicate, non-amine, non-
nitrite, and non-borate coolant with
long-life hybrid organic acid technology
Do not use plain water alone.
Ignition system (spark plug)
MakeDENSO FC16HR-CY9
Gap0.035 in. (0.9 mm)
NOTICE
■ Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark pl ug gap.
Electrical system (12-volt battery)
Open voltage at 68F (20 C):
12.0 V or higher
If the voltage is lower than the standard
value, charge the battery. (After charging
the battery, turn on the high beam head-
lights for 30 seconds with the power switch
off, and turn the headlights off.)
Charging rates5 A max.